Bradley Book Symposium: The Discussion of Customary International Law

[Mark Weisburd is the Reef C. Ivey II Distinguished Professor of Law at UNC School of Law]

Professor Curtis Bradley’s International Law in the U.S. Legal System is an important contribution to the discussion of a topic of considerable significance.  Thorough in its coverage but accessible to readers with little familiarity with the subject, it is at once an excellent introduction (for someone with a legal background) to the issues it addresses and a useful compilation for those with some familiarity with the field.

This contribution to the symposium addresses Bradley’s chapter on the place of customary international law (CIL) in the federal law of the United States.  The space available precludes my considering all of the subjects of Bradley’s chapter, and I will therefore confine my comments to two of them:  first, the implications of Sosa v. Alvarez-Machain for the methods federal judges use in identifying rules of CIL; second, current controversies over the generation of rules of CIL as a matter of international (not American domestic) law.

Much of the discussion of Sosa has focused on its analysis of 28 U.S.C. § 1350, the Alien Tort Statute.  Also important, however, was its critique of the approach the lower federal courts were taking in determining the content of CIL.  In the course of its explanation of its rejection of the respondent’s claim regarding the existence of a particular rule of CIL,  the Court noted that the respondent’s position relied in part on decisions of the lower federal courts.  The Court rejected that element of his argument, observing that, ” the authority from the federal courts, to the extent it supports Alvarez’s position, reflects a more assertive view of federal judicial discretion over claims based on customary international law than the position we take today.”  In other words, the lower courts were going too far, ascribing legal status to rules not clearly deserving of that status.  This conclusion naturally raises the question of how those courts could reach these erroneous conclusions.  The Supreme Court’s statement suggests that those courts were looking in the wrong places in trying to determine the content of CIL.  But where were they looking?

When one examines the cases whose approach Sosa criticized, one is struck by the insularity of their consideration of what is, after all, international law.  The sources those courts cite in their assertions of the content of CIL include, most prominently, decisions by other federal courts.  Scholarly articles appearing in American publications are also important, as is the Restatement Third of the Foreign Relations Law of the United States.  There also references to the Universal Declaration of Human Rights and to the International Covenant on Civil and Political Rights (instruments upon which the Sosa court itself refused to rely because of the non-binding character of the first and the non-self-executing character of the second).  Prominent by its absence is any consideration of relevant actions by other states – judicial decisions, executive pronouncements, diplomatic protests.  Sosa, then, seems to require American courts to consider state practice in determining the content of a body of law which is described as derived from state practice.

The question of current controversies regarding the generation of CIL is not one Bradley discusses in any detail.  His book, after all, is an analysis of the U.S. legal system, not the international legal system.  It seems useful, however, to address those controversies very briefly, especially in light of Sosa‘s insistence on a careful consideration of the basis for claims that particular rules are well-established elements of CIL.

As Bradley notes, these controversies tend to arise from disagreements as to what behavior should count as satisfying the “state practice” component of a rule of CIL.  He points out that, whereas CIL is traditionally induced from widespread state behavior, modern approaches are “often more deductive in character, and involve reliance on treaties, international resolutions, scholarly opinion, and similar materials.  The emphasis under this approach tends to be on the “sense of legal obligation” component of CIL…”

It is Bradley’s purpose to alert the reader to the existence of these disagreements rather than to address them himself.  There are, however,  at least two points that might be made about the modern approaches to the determination of CIL.  First, those who see the materials Bradley mentions as evidencing a sense of legal obligation seem to rely on a non sequitur.  Certainly, a state that becomes a party to a treaty has assumed a legal obligation, but it is not obvious that adherence to a treaty provides any information about that state’s understanding of its legal obligations dehors the treaty.  International resolutions are, by definition, non-binding; again, it is not clear why a state’s support for a resolution it knows creates no legal obligation amounts to evidence that the states sees itself as legally bound.  Finally, scholarly writing may be useful in identifying various elements of state behavior, but the “sense of legal obligation” at issue is that of the states; scholars’ belief that certain matters ought to be a matter of legal obligation are irrelevant.

The second conundrum raised by these modern approaches is that of discovering the process by which they became jurisgenerative.  One can understand the traditional approach to CIL as giving rise to legal obligations because consistent practice over a period of time can create reasonable expectations that future practice will be in line with that of the past.  One can therefore understand how violation of those expectations can come to be seen as a violation of law.  But what expectations can be created by, for example, non-binding acts, especially when those acts are contradicted by states’ actual behavior?  And if the status as law of rules deduced from the sources Bradley mentions does not result from the creation of reasonable expectations, what is the basis for ascribing legal status to those rules?

Much more could be said about Curtis Bradley’s discussion of the place of CIL in American law, but this is a comment, not a book.  Read what Bradley writes.